Nature Energy, Published online: 28 August 2026; doi:10.1038/s41560-026-02122-6

Elastocaloric cooling in shape memory alloy films is efficient but limited by electrically powered actuators. Here the authors demonstrate a heat-driven system that achieves a temperature span of up to 12.9 K (4.0 K at device level), showing that waste heat can be used for electricity-minimized cooling.